Looked it up, says 'Will be released as an open source project' but announcement was in July 2025 and no public repo yet which is strange, so time will tell if they will stick to this.

https://planetscale.com/blog/planetscale-for-postgres#vitess...

https://planetscale.com/neki

...

Supabase one is open from start:

https://github.com/multigres/multigres

https://multigres.com/

We are already moving Neki customers into production. Nobody else is even close. PlanetScale doesn't spend our days yapping about what we are going to do. We just do it.